Problem: $-6u + 8v - 6w - 9 = v + 2w - 7$ Solve for $u$.
Explanation: Combine constant terms on the right. $-6u + 8v - 6w - {9} = v + 2w - {7}$ $-6u + 8v - 6w = v + 2w + {2}$ Combine $w$ terms on the right. $-6u + 8v - {6w} = v + {2w} + 2$ $-6u + 8v = v + {8w} + 2$ Combine $v$ terms on the right. $-6u + {8v} = {v} + 8w + 2$ $-6u = -{7v} + 8w + 2$ Isolate $u$ $-{6}u = -7v + 8w + 2$ $u = \dfrac{ -7v + 8w + 2 }{ -{6} }$ Swap the signs so the denominator isn't negative. $u = \dfrac{ {7}v - {8}w - {2} }{ {6} }$